This invention relates to the art of water purification and more particularly to a filtering system for treating rain water run-off.
The Chesapeake Bay is in crisis because of pollutants from a variety of sources. A major contributor to bay pollution is rain water which runs off of large buildings roofs and parking lots during a storm. Heavy rains rinse these surfaces of accumulated contaminants, flushing them quickly into the bay through storm sewers designed to handle heavy flow rates.
Riparian owners downstream of commercial developments note increased stream volume and flooding during storms. Such areas are designed to shed water, rather than permitting it to soak into the ground where it falls. The effect is the antithesis of a pond system, which catches moderate runoff and allows it to soak into the ground without flooding nearby streams.
It would be beneficial to riparian owners, and, we believe, to the environmental health of the bay, to simulate a pond system in highly developed areas where open ponds are impractical.
Prior inventors have developed a number of water treatment tanks, for example oil-water separators, many containing an aggregate for coalescing oil, or other purpose. This invention is not aimed so much at oil separation as flow control and phosphorus removal. Nevertheless, patents such as U.S. Pat. Nos. 3,962,084, 4,783,272, 4,985,148, 5,017,044, 5,073,261, 5,204,000, 5,330,651, 5,50,132 and 5,503,747 are of interest.